Two lions at the Zagreb zoo have tested positive for COVID-19 that they had contracted from their keeper, officials said on Wednesday.

These are the first confirmed cases of the disease in zoo animals in Croatia, an agriculture ministry statement said.

Laboratory tests on samples taken from the two animals after they had developed symptoms of the disease confirmed that they have COVID-19, it said.

The big cats, who are undergoing medical treatment, caught the infection from their keeper who was also tested afterwards and was positive, head of the zoo Damir Skok said.

"The zookeeper as well as (lions) Leo and Ayana are fine. They sneeze and cough occasionally" and are recovering, he told local media.

Zoo visitors cannot contract the coronavirus from the lions as they are kept behind a glass fence, he added.

Other animals that the keeper was taking care of were also tested for COVID-19 and results of the tests are excepted soon.

In September, several US zoos, including the one in Washington, launched a vaccination campaign for animals susceptible to COVID-19 after a bout of sickness among them.

Croatia, which has some of Europe's lowest inoculation rates, is currently facing a record surge of coronavirus infections since the start of the pandemic.

The respiratory disease has claimed more than 10,000 lives in the country of 4.2 million people.